In a tweet on Monday, Trump said: "We cannot let those killed in El Paso, Texas, and Dayton, Ohio, die in vain."

"Republicans and Democrats must come together and get strong background checks, perhaps marrying this legislation with desperately needed immigration reform," Trump continued. "We must have something good, if not GREAT, come out of these two tragic events!"

It wasn't immediately clear which specific pieces of legislation Trump was advocating in his messages.

What we know about the El Paso shooting

Seven Mexican citizens died in the shooting, according to the office of the Mexican Secretary of Foreign Affairs Marcelo Ebrard.

Another victim, Jordan Anchondo, 24, died while shielding her 2-month-old son, her aunt Liz Terry told CNN. Her husband, Andre Anchondo, 23, was also killed in the shooting. The family was shopping for school supplies when the gunman opened fire.

Jordan and Andre Anchondo died in the shooting in El Paso. Photo: Family Handout

The suspect -- who sources identified to CNN as Patrick Crusius of Allen, Texas -- has been charged with capital murder and is being held without bond, El Paso Police Sgt. Robert Gomez said.

Authorities believe Crusius is the author of a racist, anti-Hispanic document detailing motivations for the shooting.

6:24 a.m. ET, August 5, 2019

Students asked to wear white in solidarity with the victims

Socorro Independent School District in El Paso County asked its students and staff to wear white on Monday in solidarity with the victims of the shooting.

The Socorro Independent School District oversees more than 47,000 students in 49 schools.

5:37 a.m. ET, August 5, 2019

El Paso Bishop warns against divisions

From Rosa Flores, CNN

El Paso Bishop Mark Seitz has warned that an attitude that sets different groups of people against one another "will only lead to more and more conflict."

Speaking to CNN on Sunday, Seitz, of the Catholic Diocese of El Paso, said:

Clearly everyone agrees that we want an orderly process for crossing a border, but when we start looking at immigrants as a threat to our country…then we’ve really got something terribly wrong.”

Seitz has long been an outspoken critic of what he called the "militarization of the border."

In a 2017 pastoral letter, Seitz denounced the "indefensible, hateful words towards our neighbors in Mexico, the demonization of migrants, and destructive language about our border."

On Sunday, he said:

We see what can happen when we start dividing people according to the color of their skin, according to their nationality, the language that they speak and whether they have documents for this country or not.”

4:22 a.m. ET, August 5, 2019

Shooter faces death penalty in "domestic terrorism case"

Federal authorities are treating the El Paso mass shooting as a case of domestic terrorism, the US Attorney for the Western District of Texassaid.

Two more victims from El Paso identified by family

Leo Campos and Maribel Hernandez are among the 20 killed in the shooting at a Walmart in El Paso, family told CNN affiliate KFOX/KDBC.

Maribel Hernandez's brother Al Hernandez said the two dropped their dog off at the groomers before going shopping at the Walmart on Saturday.

The brother said they knew something was wrong when the groomer called and said Campos and Hernandez had not picked up their dog. One of their family members was able to track the GPS of their vehicle to the Walmart parking lot.

Hernandez said police notified them on Sunday that both had died, KFOX/KDBC reported.

1:47 a.m. ET, August 5, 2019

The number of Mexicans killed in the shooting rises to 7

From CNN’s Jonny Hallam

Seven Mexican nationals were killed in the El Paso shooting on Saturday, according to Mexican Secretary of Foreign Affairs Marcelo Ebrard.

Ebrard said on his Twitter page Sunday evening the seventh Mexican national is Ivan Filiberto Manzano from Ciudad Juárez, Chihuahua.

Previously, six Mexicans were confirmed to have died in the shooting.

The victims are as follows:

Sara Esther Regalado,Cd. Juárez, CHIH.

Adolfo Cerros Hernández,Aguascalientes, AGS.

Jorge Calvillo García,Torreón, COAH.

Elsa Mendoza de la Mora, Yepomera, CHIH.

Gloria Irma Márquez,Juárez, CHIH

María Eugenia Legarreta,Chihuahua, CHIH.

Iván Filiberto Manzano,Cd. Juárez, CHIH.

Mexico's President Andrés Manuel López Obrador said on Sunday that seven other Mexicans are injured.

Here's what we know so far about those who were injured:

Mario de Alba Montes, 45, of Chihuahua, was shot in the back

Olivia Mariscal Rodriguez, 44, of Chihuahua, was injured in the chest and hand

Erika de Alba Mariscal, 10, was injured in the leg

12:50 a.m. ET, August 5, 2019

Family and friends gather to wait for news of missing loved ones in the El Paso shooting

From CNN's Rosa Flores and Chelsea J. Carter

The Texas and American flags at the MacArthur School in El Paso, Texas, fluttered at half-staff, signaling a state and a nation in mourning.

A "Looking for Family or Friend" sign hangs above the front doors of the elementary-intermediate school. Inside, family and friends await news of loved ones they haven't seen since a gunman went on a rampage at a Walmart on Saturday, killing 20 people and wounding at least 26.

This is the place authorities designated as a reunification center in the hours after the shooting, a place for friends and family members to find one another after the chaos saw people run for their lives -- and, in so many cases, become separated.

On Sunday, it was the place where many found out a loved one was killed or wounded.

Most people who walk in and out of the school don't want to talk. When asked if they would like to share their story, they wipe away tears and say no.

Outside the building, near the marquee reminding parents to register children for school, a group of people sobbed and hugged one another.

A woman who did not want to disclose her name said she was visiting with a friend who was told her loved one had died and was waiting to learn where she needed to go to identify the body.

Still others came to the school to get information because they didn't know where else to go.